The present invention relates generally to plastic fasteners and more particularly to a needle for use in a plastic fastener dispensing tool.
Plastic fasteners of the type comprising an elongated flexible filament having a first cross-bar at one end and a second cross-bar (or other enlargement, such as a paddle or a knob) at the opposite end are well-known and have been widely used in a variety of applications, such as in the attachment of merchandise tags to articles of commerce, in the attachment of buttons to garments, in the lasting of shoes, and in various packaging applications. Typically, such plastic fasteners are mass-produced by molding processes into either one of two different types of assemblies. One such assembly, an example of which is disclosed in U.S. Pat. No. 3,103,666, inventor Bone, issued Sep. 17, 1963 (which patent is incorporated herein by reference), is a clip-type assembly, said clip comprising a plurality of fasteners, each such fastener comprising a flexible filament having a first cross-bar at one end thereof and a paddle or second cross-bar at the opposite end thereof. The fasteners are arranged in a spaced, side-by-side orientation, with the respective first cross-bars parallel to one another and the respective paddles or second cross-bars parallel to one another, each of the first cross-bars being joined to a common, orthogonally-disposed runner bar by a severable connector. Adjacent second cross-bars or paddles also may be interconnected by severable connectors extending therebetween.
The aforementioned fastener clip is typically made by injection molding. Several commercial embodiments of the above-described fastener clip have been sold by the present assignee, Avery Dennison Corporation, as DENNISION(copyright) SWIFTACH(copyright) fastener clips.
Tools (often referred to as xe2x80x9ctagging gunsxe2x80x9d or xe2x80x9cfastener attaching toolsxe2x80x9d) for dispensing individual fasteners from fastener clips of the type described above are known, examples of such tools being disclosed in the following U.S. patents, all of which are incorporated herein by reference: U.S. Pat. No. 3,895,753, inventor Bone, issued Jul. 22, 1975; U.S. Pat. No. 4,611,740, inventor Kunreuther, issued Sep. 16, 1986; and U.S. Pat. No. 3,893,612, inventor Bone, issued Jul. 8, 1975.
Such tools typically comprise a needle, the needle typically including a stem and a base. The stem, which is typically made from stamped and rolled metal, typically has a front portion and a rear portion. The front portion is generally cylindrical in shape and has a longitudinally-extending, cylindrically-shaped bore adapted to receive the first cross-bar of a fastener. In addition, the front portion of said stem also typically has a longitudinally-extending slot adapted to permit the filament portion of a fastener to extend therethrough while the first cross-bar of the fastener is disposed in the longitudinal bore. The front portion of the stem also typically terminates at its front end in a tip adapted for insertion into a desired article of commerce. The rear portion of the stem is typically shaped to include a cutting element or knife along its rear edge for cutting the severable connector connecting the runner bar to the cross-bar as the cross-bar is being loaded into the longitudinal bore. Typically, said knife is in the form of a V-shaped notch having an internal angle of about 75 degrees and a width of about 0.025 inch.
The base of the needle is typically made of molded plastic and is mounted onto the rear portion of the stem. The base is typically a generally cylindrical member having a longitudinal bore aligned with the longitudinal bore of the stem and having a longitudinal slot aligned with the longitudinal slot of the stem. The base also typically has a lateral slot adapted to permit part of the cross-bar to be fed into the base from the side and also includes a recess formed on the outer surface of the base adapted to engage a locking mechanism in a tool. The base also typically has a cutout at the rear end thereof that is in alignment with the notch of the stem and which serves to prevent the base from interfering with the operation of the notch.
Although the above-described needle is a two-part structure, corresponding needles have also been formed as unitary structures machined from a single piece of metal.
Examples of the needles described above are disclosed in the following patents, all of which are incorporated herein by reference: U.S. Pat. No. 4,333,596, inventor Kunreuther, issued Jun. 8, 1982; U.S. Pat. No. 4,611,740, inventor Kunreuther, issued Sep. 16, 1986; and U.S. Pat. No. 3,895,753, inventor Bone, issued Jul. 22, 1975.
One problem that has been noted by the present inventor with respect to the dispensing of individual fasteners from fastener clips of the type described above using needles of the types described above is that there is occasionally some difficulty in properly aligning the severable connector with the cutting notch on the needle. In these instances, the connector is often advanced in a tool past the cutting notch, thereby resulting in considerably higher cutting resistance and, as a result, in jamming of the tool.
One approach to the aforementioned problem is disclosed in U.S. Pat. No. 5,715,984, inventor Deschenes, which issued Feb. 10, 1998, and which is incorporated herein by reference. In said patent, there is described a needle for use as part of a fastener dispensing tool, said needle comprising a substantially cylindrical base portion having a front end, a rear end, a side surface, a central bore, and a longitudinal slot. The needle also includes a stem portion extending out from the front end of the base portion. The stem portion is a substantially cylindrically shaped member which comprises a sharp tip, a longitudinal slot in alignment with the longitudinal slot in the base portion, and a central bore in alignment with the central bore in the base portion. The needle further includes a knife portion on the rear end of the base portion. The knife portion has a pair of side edges and a back edge, the back edge including a cutting edge in the form of a notch, said notch extending across the entire length of the back edge from one side edge to the other side edge.
It is an object of the present invention to provide a novel needle for use in a plastic fastener dispensing tool.
It is another object of the present invention to provide a needle as described above that overcomes at least some of the disadvantages discussed above in connection with certain existing needles.
It is still another object of the present invention to provide a needle as described above that can be mass produced and that can be used in conventional plastic fastener dispensing tools.
According to one feature of the invention, there is provided a needle for use in a plastic fastener dispensing tool, said needle comprising (a) a stem, said stem being elongated and having a front portion and a rear portion, said front portion being shaped to include a slotted longitudinal bore terminating in a tip at its front end, said rear portion having a knife implement in the form of a notch at its rear end, said notch being asymmetric about the longitudinal axis of said slotted longitudinal bore; and (b) a base, said base being mounted onto said rear portion of said stem, said base being shaped to include a slotted longitudinal bore aligned with said slotted longitudinal bore of said stem.
According to another feature of the invention, there is provided a needle for use in a plastic fastener dispensing tool, said needle comprising (a) a stem, said stem being elongated and having a front portion and a rear portion, said front portion being shaped to include a slotted longitudinal bore terminating in a tip at its front end, said rear portion having a rear end, said rear end being shaped to include a knife implement in the form a notch, said notch extending only partially across said rear end, said notch having an internal angle of approximately 110-145 degrees; and (b) a base, said base being mounted onto said rear portion of said stem, said base being shaped to include a slotted longitudinal bore aligned with said slotted longitudinal bore of said stem.
According to still another feature of the invention, there is provided a needle for use in a plastic fastener dispensing tool, said needle comprising (a) a stem, said stem being elongated and having a front portion and a rear portion, said front portion being shaped to include a slotted longitudinal bore terminating in a tip at its front end, said rear portion having a rear end, said rear end being shaped to include a knife implement in the form of a notch, said notch having a width of approximately 0.050-0.08 inch; and (b) a base, said base being mounted onto said rear portion of said stem, said base being shaped to include a slotted longitudinal bore aligned with said slotted longitudinal bore of said stem.
According to still yet another feature of the invention, there is provided a needle for use in a plastic fastener dispensing tool, said needle comprising (a) a base portion, said base portion having a front end, a rear end, and a slotted longitudinal bore; (b) a stem portion extending out from the front end of said base portion, said stem portion having a slotted longitudinal bore aligned with the slotted longitudinal bore in said base portion; and (c) a knife portion on said base portion, said knife portion having a pair of side edges and a back edge, the back edge including a cutting implement in the form of a notch; (d) wherein said notch is asymmetric about the longitudinal axis of said slotted longitudinal bore of said stem portion.
According to even yet another feature of the invention, there is provided a needle for use in a plastic fastener dispensing tool, said needle comprising (a) a base portion, said base portion having a front end, a rear end, and a slotted longitudinal bore; (b) a stem portion extending out from the front end of said base portion, said stem portion having a slotted longitudinal bore aligned with the slotted longitudinal bore in said base portion; and (c) a knife portion on said base portion, said knife portion having a pair of side edges and a back edge, the back edge including a cutting implement in the form of a notch; (d) wherein said notch extends only partially across said back edge from one side edge to the other side edge, said notch having an internal angle of about 110-145 degrees.
According to a further feature of the invention, there is provided a needle for use in a plastic fastener dispensing tool, said needle comprising (a) a base portion, said base portion having a front end, a rear end, and a slotted longitudinal bore; (b) a stem portion extending out from the front end of said base portion, said stem portion having a slotted longitudinal bore aligned with the slotted longitudinal bore in said base portion; and (c) a knife portion on said base portion, said knife portion having a pair of side edges and a back edge, the back edge including a cutting implement in the form of a notch; (d) wherein said notch extends only partially across said back edge from one side edge to the other side edge and has a width of about 0.50-0.08 inch.
According to still a further feature of the invention, there is provided a needle for use in a plastic fastener dispensing tool, said needle comprising (a) a base portion, said base portion having a front end, a rear end, and a slotted longitudinal bore; (b) a stem portion extending out from the front end of said base portion, said stem portion having a slotted longitudinal bore aligned with the slotted longitudinal bore in said base portion; and (c) a knife formed in the rear end of said base portion, said knife being in the form of a notch; (d) wherein said notch is asymmetric about the longitudinal axis of said slotted longitudinal bore of said stem portion.
According to still yet a further feature of the invention, there is provided a needle for use in a plastic fastener dispensing tool, said needle comprising (a) a base portion, said base portion having a front end, a rear end, and a slotted longitudinal bore; (b) a stem portion extending out from the front end of said base portion, said stem portion having a slotted longitudinal bore aligned with the slotted longitudinal bore in said base portion; and (c) a knife formed in the rear end of said base portion, said knife being in the form of a notch; (d) wherein said notch extends only partially across said rear end, said notch having an internal angle of about 110-145 degrees.
According to still even yet a further feature of the invention, there is provided a needle for use in a plastic fastener dispensing tool, said needle comprising (a) a base portion, said base portion having a front end, a rear end, and a slotted longitudinal bore; (b) a stem portion extending out from the front end of said base portion, said stem portion having a slotted longitudinal bore aligned with the slotted longitudinal bore in said base portion; and (c) a knife formed in the rear end on said base portion, said knife being in the form of a notch; (d) wherein said notch extends only partially across said rear end and has a width of about 0.50-0.08 inch.
Additional objects, features, aspects and advantages of the present invention will be set forth, in part, in the description which follows and, in part, will be obvious from the description or may be learned by practice of the invention. In the description, reference is made to the accompanying drawings which form a part thereof and in which is shown by way of illustration specific embodiments for practicing the invention. These embodiments will be described in sufficient detail to enable those skilled in the art to practice the invention, and it is to be understood that other embodiments may be utilized and that structural changes may be made without departing from the scope of the invention. The following detailed description is, therefore, not to be taken in a limiting sense, and the scope of the present invention is best defined by the appended claims.